<!DOCTYPE html>
<html lang="en">

<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>Document</title>
  <script src="./opfs.js"></script>
</head>

<body>
  <button id="opfs1">opfs1</button>
  <button id="opfs2">opfs2</button>
  <script>
    document.getElementById("#opfs1").addEventListener("click", function () {
      opfs();
    });
    document.getElementById("#opfs2").addEventListener("click", function () {
      const worker = new Worker('./opfs worker.js');
    });
  </script>
</body>

</html>